[jdkramar]

This also bothered me. Just reading through his blog post makes it clear that proper English isn't very high on his list of priorities.

[benpof]

Whoops, my bad, it's been fixed with the % sign.

[tripzilch]

You might also want to consider using promille (per 1000) or something similar, when dealing with such tiny percentages. (I don't mean they're tiny for a CTR figure, just that small numbers like that are harder to get a gist of than "1.37 clicks for each 1000 views".